Infants' Attention to Patterned Stimuli: Developmental Change From 3 to 12 Months of Age

Abstract

To examine the developmental course of look duration as a function of age and stimulus type, 14-to 52-week-old infants were shown static and dynamic versions of faces, Sesame Street material and achromatic patterns for 20 seconds of accumulated looking. Heart rate was recorded during looking and parsed into stimulus orienting, sustained attention, and attention termination phases of attention. Infants' peak look durations indicated that prior to 26 weeks there was a linear decrease with age for all stimuli. Older infants' look durations continued to decline for patterns but increased for Sesame Street and faces. Measures of heart rate change during sustained attention and the proportion of time spent in each phase of attention confirmed infants' greater engagement with the more complex stimuli.Infants' Attention to Patterned Stimuli: Developmental Change from 3 to 12 Months of Age Measures of visual attention obtained from habituation and selective looking (e.g., pairedcomparison; novelty preference) procedures have provided a wealth of information about the development of infants' sensory, perceptual, and cognitive capabilities (for reviews see Haith & Benson, 1998;Kellman & Banks, 1998). More recently, these procedures have become important in their own right with growing evidence that components of infants' attention during habituation and selective looking also provide information about the functioning and early development of the human information-processing system (see Bornstein, 1998;Colombo, 1993;Fagan, 1990;Hayne, 2004;McCall, 1994;Rose, Feldman, & Jankowski, 2004). The underlying reasoning is not new and is based on the assumption that the process of habituation represents a ubiquitous and elementary form of learning during which the infant constructs an internal representation (trace, or engram) of an external stimulus. As the infant's attention to the stimulus progresses and its representation becomes complete, his or her attention to it wanes. The subsequent presentation of a novel stimulus elicits a recovery of attention (dishabituation, or a novelty preference) as the infant presumably compares its features to the internal representation of the familiar stimulus, "recognizes" at some level that it is unrepresented or weakly represented in memory, and begins the process of trace construction once more (Sokolov, 1963). These same familiarization, comparison, and recognition processes are also presumed to occur without complete habituation, as infants will show visual preference for a novel stimulus even after fairly brief exposure to a standard (see Fagan,

Changes in behavior and salivary cortisol after targeted cognitive training in typical 12-month-old infants.

“…Also, the finding that training led to longer look durations may be seen as surprising given that, in younger (<9-month-old) infants, look duration is negatively associated with long-term cognitive outcomes. However, Courage and colleagues have suggested that voluntary attention control becomes an increasingly important influence on looking behaviour, starting from 12 months, such that increased voluntary attention control is associated with longer look durations towards novel objects (Courage, Reynolds, & Richards, 2006). Thus, increased initial look duration and a faster subsequent fall-off of looks may both be effects of increased endogenous (voluntary) control over orienting behaviours as a result of training.…”

Stress reactivity speeds basic encoding processes in infants

“…The most common measure is the duration of the infant's peak, or longest, look. Behavioral studies with human infants indicate that looking time to both simple and complex stimuli decrease with age until about six months, whereas look durations to more complex stimuli, such as videos and picture of faces, starts to increase starting at around six months (Courage, Reynolds, & Richards, 2006). …”

Early Development of Executive Attention

“…By 3 months of age, babies are able to disengage attention from a central stimulus [60], significantly diminishing the time they need to disengage between 4 and 6 months of age [61]. Infants from 6 months of age regulate their attention differently according to whether the stimuli are boring (habituating more rapidly) or engaging (increasing the time they expend looking at it), also reflecting an initial endogenous control of attention [62].…”